/Engine/Source/Runtime/Interchange/Core/Public/InterchangePipelineBase.h
Return a mutable property states Reference. Add the property states if it doesnt exist.
[FInterchangePipelinePropertyStates](API\Runtime\InterchangeCore\FInterchangePipelinePropertyStat-_1) & FindOrAddPropertyStates ( const [FName](API\Runtime\Core\UObject\FName) PropertyPath )